DETAILED ACTION
Notice of Pre-AIA or AIA Status
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
This is a Final Office Action in response to amendment filed on 03/02/2026.
Claim Status
Claims 1, 5, 7,and 13-20 are pending. Claims 13-20 are withdrawn as a result of Restriction Requirement. Claims 1, 5, and 7 are currently amended. Claims 2-4, 6, and 8 are currently canceled. Claims 1, 5 and 7 are examined on the merits.
Response to Amendment
The rejection of Claims 1-2, and 5-8 rejected under 35 U.S.C. 112(b) are withdrawn in view of amendment to the claims.
The rejection of Claims 1, 2, 5 and 8 rejected under 35 U.S.C. 112(a) is withdrawn in view of amendment to the claims.
The rejection of Claim 1 rejected under 35 USC § 102(a)(1) is withdrawn in view of amendment to the claims. However, claim 1 is now rejected under 35 U.S.C. §103 for the reasons set forth below.
The rejection of claim 2, 6, and 8 rejected under 35 U.S.C. §103 is withdrawn in view of the cancellation of claim 2, 6, and 8.
Claim Rejections - 35 USC § 103
The following is a quotation of 35 U.S.C. §103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
Claims 1, 5, and 7 are rejected under 35 U.S.C. §103 as being unpatentable over Zhou (Jie Zhou et. al., Plant Physiology (2008) Volume 146, Issue 4, pp1673–1686), in view of Yang (Shu-Yi Yang et. all., The Plant Cell (2012), Volume 24, Issue 10, pp4236–4251) and in view of Wu (Ping Wu et. al., Current Opinion in Plant Biology (2013) Volume 16, Issue 2, pp 205-212).
Applicant’s amendment has been fully considered. In view of the amendment to claim 1, the prior rejection of claim 1 under 35 USC § 102(a)(1) is withdrawn. Nevertheless, claim 1 is now rejected under 35 U.S.C. §103 as being unpatentable over Zhou (2008), Yang (2012) and Wu (2013) for the reasons set forth below.
Claim 2, 6, and 8 have been canceled. Accordingly, the rejection of claims 2, 6, and 8 under 35 U.S.C. §103 is withdrawn. The rejection of claims 5 and 7 under 35 U.S.C. §103 is maintained for the reasons of record set forth in the office action mailed 12/10/2025, with further explanation provided below. Applicants’ arguments filed on 3/2/2026 have been considered but are not deemed persuasive.
Claim 1 recites a method for regulating symbiosis between Gramineous plants and arbuscular mycorrhizal fungi, and regulating the inhibitory effect of phosphate on arbuscular mycorrhizal symbiosis, the method comprises: regulating gene expression or protein activity of phosphate starvation response factor PHR2 in Gramineous plants selected from:
a) up-regulating the gene expression or protein activity of phosphate starvation response factor PHR2 in Gramineous plants, thereby promoting the symbiosis of plants and arbuscular mycorrhizal fungi, and antagonizing the inhibitory effect of phosphate on arbuscular mycorrhizal symbiosis, wherein said up-regulating the gene expression or protein activity of phosphate starvation response factor PHR2 comprises transferring the encoding sequence of phosphate starvation response factor PHR2 into the Gramineous plants; wherein the PHR2 is selected from a polypeptide having the amino acid sequence of SEQ ID NO: 2.
The present rejection is based on embodiment (a) of claim 1; embodiment (b) is not relied upon in this rejection.
Zhou teaches a phosphate starvation response factor in rice, OsPHR2, and demonstrates that OsPHR2 is a central regulator of the phosphate starvation signaling pathway (page 1673, Abstract). Blast search shows SEQ ID NO:2 in instant application is 100% align with Phosphate Starvation Response Protein 2 in rice (OSPHR2) (check NCBI Blast result below). Zhou teaches that over expression of OsPHR2 in rice increases phosphate accumulation in both phosphate-deficient and phosphate-sufficient conditions (page 1676, left column, paragraph 3), and activates phosphate starvation-inducible (PSI) genes even under phosphate-sufficient conditions (1681, fig 8). Zhou specifically teaches that PHR2 overexpression maintains activation of downstream PSI regulatory pathways despite high phosphate supply, indicating that PHR2 can antagonize or override phosphate suppression of Pi acquisition pathways. Zhou further teaches overexpression of OsPHR2 up-regulates several Pi Transporters (PHT, or PT) (page 1679, left column paragraph 2). In OsPHR2-overexpressing plants, a remarkable up-regulation of these genes was observed at high phosphate levels in shoots compared with wild-type plants (OsPT1(PHT1:1), OsPT5, OsPT7, OsPT9, and OsPT12 were examined) , which might be associated with increased Pi translocation into shoots (page 1682, and figure 9).
Zhou does not expressly teach that OsPHR2 overexpression promotes AM symbiosis or overcomes phosphate-mediatized suppression.
Yang teaches that PT11 and PT13 are symbiosis-specific phosphate transporter genes in rice associated with arbuscular mycorrhizal symbiosis (page 4236, Abstract). Yang further teaches that both PT11 and PT13 are important for development of AM symbiosis, and that PT11 is necessary and sufficient for symbiotic phosphate uptake in rice (page 4236, Abstract). Yang also teaches that PT11 expression is associated with arbusculated cells (page 4237, left column, paragraph 2) and that higher phosphate suppresses PT11 expression and colonization (page 4246, left column paragraph 1), reflecting the known inhibitory effect of phosphate on AM symbiosis. Thus, Yang teaches that PT11 is a key downstream component of AM symbiosis and symbiotic phosphate acquisition in rice, and that AM symbiosis is negatively regulated by phosphate availability. Yang does not use the term “antagonize,” but it clearly links AM symbiosis and PT11 function to improved phosphate uptake efficiency.
Wu teaches that PHR2 is a transcription factor that binds P1BS in the promoter of phosphate starvation-induced phosphate transporter genes (e. g., OsPTs (PTs), page 206) and that overexpression of PHR2 induces expression of these OsPT genes, including PT11 (page 206, left column paragraph 3). Thus, Wu explain the mechanism by which PHR2 activation results in increased expression of phosphate transporters that mediate phosphate uptake into the plant.
It would have been obvious to one of ordinary skill in the art at the time of the invention to modulate OsPHR2 expression to improve phosphate uptake, to overexpress OsPHR2 in rice, as taught by Zhou, in view of Yang’s teaching that PT11 is a central AM-symbiosis-specific phosphate transporter necessary for symbiotic phosphate uptake, and Wu’s teaching that OsPHR2 promotes PT11 expression, because a skilled artisan would have understood OsPHR2 to be an upstream regulator of phosphate-responsive pathways and would have been motived to modulate OsPHR2 in order to affect downstream phosphate transport components involved in AM symbiosis.
A person of ordinary skill in the art would have had a reasonable expectation that increasing expression of the upstream phosphate-response regulator OsPHR2 would increase expression of the downstream symbiosis-associated phosphate transporter PT11, thereby influencing AM-associated phosphate uptake and symbiotic function in rice. In view of Yang’s further teaching that high phosphate suppresses PT11-assocaited AM colonization, it would have been obvious to use OsPHR2 up-regulation to modulate this phosphate-responsive symbiotic pathway.
Claim 5 is drawn to the method of claim 1, wherein the regulation of symbiosis between Gramineous plants and arbuscular mycorrhizal fungi or the regulation of inhibitory effect of phosphate on arbuscular mycorrhizal symbiosis comprises up-regulating gene expression or protein activity of PHR2 under low-phosphate conditions, promoting symbiosis between plants and arbuscular mycorrhizal fungi, and increasing phosphate uptake.
Claim 5 is rejected for the same reasons set forth with respect to claim 1.
Zhou teaches that overexpression of the phosphate starvation response factor PHR2 in rice plants increase phosphate accumulation under both low-phosphate and high-phosphate conditions (page 1676, left column, paragraph 3). Thus, Zhou teaches regulation the expression or activity of PHR2 in rice plants to enhance phosphate uptake and accumulation over a range of external phosphate levels. Zhou therefore disclose that regulation of PHR2 is used to improve phosphate acquisition efficiency in plants. Zhou further teaches overexpression of OsPHR2 up-regulates several Pi Transporters (PHT, or PT) (page 1679, left column paragraph 2).
Yang teaches the PT11 is an arbuscular mycorrhizal-associated phosphate transporter required for symbiotic phosphate uptake in rice roots (page 4236, Abstract). Yang demonstrates that AM colonization induces PT11 expression and that disruption of PT11 impairs AM-mediated phosphate uptake, thereby showing that AM symbiosis contributes substantially to efficient phosphate acquisition in plants(page 4241, right column paragraph 1). Yang does not use the term “antagonize,” but it clearly links AM symbiosis and PT11 function to improved phosphate uptake efficiency.
Wu teaches that PHR2 is a transcription factor that binds P1BS in the promoter of phosphate starvation-induced phosphate transporter genes (e. g., OsPTs (PTs), page 206) and that overexpression of PHR2 induces expression of these OsPT genes, including PT11. Thus, Wu explain the mechanism by which PHR2 activation results in increased expression of phosphate transporters that mediate phosphate uptake into the plant.
In view of Zhou and Wu, a person of ordinary skill in the art would understand that regulating PHR2 to up-regulate downstream phosphate transporter (such as these PTs identified by Wu) is a strategy to promote efficient phosphate acquisition, exactly as cited in claim 5. Thus , the general requirement in claim 5 that the claimed regulation “comprised promoting the efficient acquisition of phosphate in plants” is inherent in or at least obvious from Zhou’s PHR2-overexpressing plants, whose purpose and demonstrated effect is to increase phosphate accumulation under low and high phosphate conditions.
With respect to the preferred embodiment “up-regulating PHR2 under low-phosphate conditions, promoting symbiosis between plants and arbuscular mycorrhizal fungi, and increasing phosphate uptake,” Zhou already teaches up-regulating PHR2 under phosphate-limiting conditions to increase phosphate accumulation. Yang teaches that establishing AM symbiosis and inducing AM-associated transporters such as PT11 increases phosphate uptake efficiency (page 4239, right column last paragraph, page 4240, left and right column). Given Zhou’s teaching that PHR2 is a central regulator of the phosphate starvation response and Wu’s teaching that PHR2 activates phosphate transporters, and yang’s teaching that AM symbiosis provides an efficient phosphate-uptake route, it would have been obvious to a POSITA to use PHR2 regulation under low-phosphate conditions not only to increase direct uptake but also to promote or support AM-associated phosphate acquisition, thereby promoting symbiosis and increasing phosphate uptakes as recited in claim 5. Any explicit recitation of “promoting symbiosis…and increasing phosphate uptake” in claim 5 thus merely states the expected functional result of applying Zhou’s PHR2-overexpression strategy in the AM-competent Gramineous plants of Yang.
Claim 7 is drawn to the method of claim 1, wherein the PHR2 has a regulating function on downstream target genes, wherein the downstream target genes comprise arbuscular mycorrhizal symbiosis-specific phosphate transporter PT11; wherein the PHR2 exerts the regulating function by binding to the P1BS element of downstream target genes.
Under BRI , claim 7 requires that PHR2 regulate PT11 expression by binding to the P1BS cis-element associated with PT11.
Wu teaches that PHR2 is a transcription factor that binds to P1BS elements in the promoter of phosphate starvation-induced phosphate transporter genes (OsPTs) and activates their expression (page 206, left column, page 207 table 1). Wu specifically identifies PT11 (OsPT11, in rice) as one of these downstream target genes whose promoter contain P1BS motifs and whose expression is up-regulated by PHR2 (page 206, left column, page 207 table 1). Accordingly, Wu explicitly teaches that PHR2 has a regulating function on downstream target genes that comprise PT11, and that this regulating function is exerted by binding to the promoter region of PT11, including P1BS elements (page 206, figure 1, table 1 ), thereby meeting the mechanistic “promoter” and “P1BS element” aspect recited in claim 7.
Yang teaches that PT11 (OsPT11) is a mycorrhiza-associated phosphate transporter required for arbuscular mycorrhizal (AM) symbiotic phosphate uptake in rice. Yang shows that PT11 is specifically involved in AM-dependent phosphate uptake and that disruption of PT11 impairs this symbiotic uptake. Thus, Yang identified PT11 as a mycorrhizal symbiosis-specific phosphate transporter and links PT11 function to the promotion of AM symbiosis-associated phosphate acquisition (page 4239, right column, paragraph 2-3).
In view of Zhou, a POSITA would be motivated to regulate PHR2 in Gramineous plants to improve phosphate acquisition. Wu teaches that PHR-family transcription factors, including PHR2, regulate downstream target genes by binding to P1BS cis-elements in their promoters, and further teaches that PT 11 is one such downstream garget gene. Wu further teaches that PHR2 regulates PT11 expression by binding to P1BS elements in the PT11 promoter. Yang teaches that PT 11 functions as an arbuscular mycorrhizal symbiosis-specific phosphate transporter involved in symbiotic phosphate uptake. From these combined teachings, it would have been obviously to a POSITA to apply PHR2 regulation in Zhou’s Gramineous plants in a manner that includes regulation of PT 11 via binding to the P1Bs element of PT11, as taught by Wu, with a reasonable expectation that such regulation would affect arbuscular mycorrhizal symbiotic phosphate uptake as taught by Yang, thereby promoting symbiosis and/or reducing the inhibitory effect of sufficient phosphate on mycorrhizal symbiosis.
Response to Applicant’s Remarks:
Applicant argues that amened dependent claims 5 and 7 are unobvious over Zhou in view of Yang and Wu, and that neither Yang nor Wu cures the deficiencies of Zhou. Applicant further states that Yang involves PT11-mediated phosphate uptake in arbuscular mycorrhizal (AM) symbiosis and that Wu involved PHR regulation of PSI genes through P1BS. These arguments have been considered but are not persuasive.
As set forth in the rejection, Zhou teaches regulating PHR2 in Gramineous plants in the context of phosphate acquisition accumulation in both phosphate-deficient and phosphate-sufficient conditions. Wu teaches that PHR-family transcription factors, including PHR2, regulate downstream phosphate-responsive genes by binding to P1BS cis-elements in their promoters, and specifically teaches PT11 as such a downstream target gene. Yang teaches that PT11 is an arbuscular mycorrhizal symbiosis-specific phosphate transporter involved in symbiotic phosphate uptake, thus, the cited references collectively teach or suggest the additional limitations of amended claims 5 and 7.
With respect to claim 7 in particular, Wu teaches that PHR2 has a regulating function on downstream target genes including PT11 and that such regulation is exerted through binging to P1BS elements in the PT11 promoter, while Yang teaches that PT11 functions in AM symbiotic phosphate uptake. In view of Zhou’s teaching of regulating RHR2 in Gramineous plants to affect phosphate acquisition, it would have been obvious to a person of ordinary skill in the art to apply the known PHR2-P1BSregulatory mechanism to PT11 in Zhou’s system, with a reasonable expectation that such regulation would affect AM symbiotic phosphate uptake and thereby promote symbiosis and/or reduce the inhibitory effect of sufficient phosphate on mycorrhizal symbiosis.
Applicant does not specifically address these combined teaches, nor does Applicant explain why a person of ordinary skill in the art would not have been motivated to combine Zhou, Wu and Yang in the manner set forth in the rejection. Instead, Applicant’s arguments amount to general assertion that the references do not individually disclose the claimed invention, which is insufficient to rebut a rejection based on the combined teachings of multiple references.
Further, to the extent Applicant relies on disclosure in the specification concerning loss-of-function mutants or reduced expression of PHR2, such disclosure does not rebut the rejection of the presently claimed subject matter. The presently rejected claims 5 and 7 are directed to the claimed methods as recited, and do not positively recite the particular down-regulation/mutant embodiments described in the specification. Arguments based on unclaimed features are not persuasive of patentability of the pending claims.
Accordingly, the rejection of claims 5 and 7 under 35 U.S.C. §103 over Zhou in view of Yang and Wu is maintained.
Conclusion
No claims are allowed.
Applicant's amendment necessitated the new ground(s) of rejection presented in this Office action. Accordingly, THIS ACTION IS MADE FINAL. See MPEP § 706.07(a). Applicant is reminded of the extension of time policy as set forth in 37 CFR 1.136(a).
A shortened statutory period for reply to this final action is set to expire THREE MONTHS from the mailing date of this action. In the event a first reply is filed within TWO MONTHS of the mailing date of this final action and the advisory action is not mailed until after the end of the THREE-MONTH shortened statutory period, then the shortened statutory period will expire on the date the advisory action is mailed, and any nonprovisional extension fee (37 CFR 1.17(a)) pursuant to 37 CFR 1.136(a) will be calculated from the mailing date of the advisory action. In no event, however, will the statutory period for reply expire later than SIX MONTHS from the mailing date of this final action.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to YANXIN SHEN whose telephone number is (571)272-7538. The examiner can normally be reached Monday-Friday.
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/YANXIN SHEN/Examiner, Art Unit 1663
/WEIHUA FAN/Primary Examiner, Art Unit 1663