EX. 99.28(d)43)(xxiii)

Amendment to

Amended and Restated

Investment Sub-Advisory Agreement Between

Jackson National Asset Management, LLC

and Mellon Investments Corporation

(originally, Mellon Capital Management Corporation)

This Amendment is made by and between Jackson National Asset Management, LLC, a Michigan limited liability company and registered investment adviser (the “Adviser”), and Mellon Investments Corporation (originally, Mellon Capital Management Corporation), a Delaware corporation and registered investment adviser (the “Sub-Adviser”).

Whereas, the Adviser and Sub-Adviser (the “Parties”) entered into an Amended and Restated Investment Sub-Advisory Agreement, effective as of the 1^st day of December, 2012, as amended (the “Agreement”), whereby the Adviser appointed the Sub-Adviser to provide certain sub-investment advisory services to certain investment portfolios (each a “Fund,” and collectively, the “Funds”) of JNL Series Trust (the “Trust”), as listed on Schedule A of the Agreement.

Whereas, the Parties have agreed to amend Section 3. “Management” of the Agreement, to align with a change in administrative procedures, and Section 12. “Duration and Termination” to add clarifying language, effective January 25, 2019.

Now Therefore, in consideration of the mutual covenants herein contained, the Parties hereby agree to amend the Agreement as follows:

1) Sub-paragraph g) after “The Sub-Adviser further agrees that it:”, under Section 3. “Management,” which was updated to sub-paragraph i) in the May 30, 2013 amendment to the Agreement, shall be deleted and replaced, in its entirety, with the following:

i) will act upon reasonable instructions from Adviser (except as to the voting of proxies) not inconsistent with the fiduciary duties and investment objectives hereunder;

2) Sub-paragraph i) after “The Sub-Adviser further agrees that it:”, under Section 3. “Management,” which was updated to sub-paragraph k) in the May 30, 2013 amendment to the Agreement, shall be deleted and replaced, in its entirety, with the following:

k)       Consistent with its fiduciary duties to each Fund and on the Fund’s behalf, the Sub-Adviser is hereby appointed the Fund’s agent to exercise in its direction all rights and performs all duties with respect to the Fund’s right to vote (or refrain from voting), each Fund’s securities and exercise rights in corporate actions or otherwise in accordance with the Sub-Adviser’s proxy voting guidelines, as amended from time to time, which shall be provided to the Trust and the Adviser. For the avoidance of doubt, the Sub-Adviser will have full discretion in this regard and the Adviser will not attempt to influence the Sub-Adviser’s voting decisions. The Sub-Adviser further agrees to report significant shareholdings for itself and on behalf of the Fund where required by local law. For the avoidance of doubt, the parties acknowledge and agree that the Sub-Adviser may be restricted from purchasing certain securities as a result of regulatory limits or other restrictions.

3) Section 12. “Duration and Termination” shall be deleted and replaced, in its entirety, with the following:

Duration and Termination.  The Agreement will become effective as to a Fund upon execution or, if later, on the date that initial capital for such Fund is first provided to it and, unless sooner terminated as provided herein, will continue in effect for two years from the effective date of the initial Investment Sub-Advisory Agreement with regard to all Fund(s) covered by this Agreement.  Thereafter, if not terminated as to a Fund, this Agreement will continue from year to year through September 30^th of each successive year following the initial two year period, for each Fund covered by this Agreement, as listed on Schedule A, provided that such continuation is specifically approved at least annually by the Trust’s Board of Trustees or by vote of a majority of the outstanding voting securities of such Fund(s), and in either event approved also by a majority of the Trustees of the Trust who are not interested persons of the Trust, or of the Adviser, or of the Sub-Adviser. Notwithstanding the foregoing, this Agreement may be terminated as to a Fund at any time, without the payment of any penalty, on sixty days’ written notice by the Trust or Adviser with the consent of the Board (including a majority of the Independent Trustees), or on sixty days’ written notice by the Sub-Adviser.  This Agreement will immediately terminate in the event of its assignment.  (As used in this Agreement, the terms “majority of the outstanding voting securities”, “interested persons” and “assignment” have the same meaning of such terms as in the 1940 Act.)  Section 10 and 11 herein shall survive the termination of this Agreement.

4) Except as specifically amended hereby, the Agreement shall remain in full force and effect in accordance with its terms.

5) Each of the Parties represents and warrants to the others that it has full authority to enter into this Amendment upon the terms and conditions hereof and that the individual executing this Amendment is duly authorized to bind the respective party to this Amendment.

6) This Amendment may be executed in one or more counterparts, which together shall constitute one document.

In Witness Whereof, the Parties have caused this Amendment to be executed, effective January 25, 2019.

Jackson National Asset Management, LLC		Mellon Investments Corporation (originally, Mellon Capital Management Corporation)
By:	/s/ Mark D. Nerud	By:	/s/ Rose Huening-Clark
Name:	Mark D. Nerud	Name:	Rose Huening-Clark
Title:	President and CEO	Title:	Managing Director

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